The biggest full moon of the year will rise Saturday (May 5) as Earth’s only satellite swings into its perigee, or closest approach to Earth. This so-called “supermoon” will appear extra big and extra bright. In honor of the moon’s big show, we’re dispelling a few myths about the Earth’s rocky satellite:

Myth 1: The Moon Makes Us Crazy

The word lunacy traces its roots to the word “lunar,” and plenty of people, from nurses to police officers, will tell you that things get wild around the full moon. But this non-supernatural equivalent of the werewolf myth doesn’t hold water. A 1985 review of the literature on the timing of mental illness and the moon found that the folklore that links the full moon with mental breakdowns, criminal behavior and other disturbances has no basis in scientific data.

Myth 2: The Supermoon Can Cause Disasters

The reason we have supermoons is because the moon’s orbit is not perfectly circular. When it swings closer to Earth on its elliptical path, the moon does exert a bit more of a gravitational pull on our planet. But it’s nothing Earth can’t handle.

Myth 3: The Moon Landing Was a Hoax

As thinly sourced as it is, the hoax theories can be frustrating to those who risked their lives to get to the moon. In 2002, Buzz Aldrin, one of the members of the original 1969 Apollo 11 mission, was dogged by conspiracy theorist Bart Sibrel at an event. When Sibrel blocked Aldrin’s path and called him a “coward” and a “liar,” the then-72-year-old astronaut punched Sibrel in the face.

What other myths about the moon have you encountered? Feel free to share them with us!

A collision with an asteroid might have set the planet Mercury whirling oddly in its orbit, a new study suggests.

Scientists had long assumed that Mercury was tidally locked with the sun — the planet’s tiny size and proximity to the sun suggested the star’s gravitational pull would quickly force Mercury into such a state. However, radar observations of Mercury surprisingly revealed that the planet led a far stranger life, rotating three times on its axis for every two orbits it completes around the sun. Now, researchers suggest that Mercury was once tidally locked, initially spinning in the opposite direction to its orbit.

“Mercury once had a spin rate synchronous with the sun, like the moon with the Earth,” study co-author Alexandre Correia, a planetary scientist at the University of Aveiro in Portugal, told SPACE.com.

Computer models suggest that a giant impact from an asteroid then knocked it into its current strange configuration. Evidence of this collision might include Caloris Basin, Mercury’s largest impact crater, which matches the predicted size, age and location of the impact, the researchers said. “It is the perfect candidate,” Correia said.

Such an impact might also explain certain hollows seen on Mercury’s surface. If the planet was tidally locked, one side would have been extremely bright and hot while the other extremely dark and cold. Substantial deposits of ice might have accumulated on the dark half, some of which might have been buried under matter ejected from impacts. When Mercury’s spin later changed and daylight began falling on the once dark side, this buried ice might have vaporized, leaving behind hollows, the researchers explained.

The results of the study were published online today (Dec. 11) in the journal Nature Geoscience.